The present invention relates to fasteners and, more particularly, to bolts with a cleaning point.
When a bolt is screwed into a threaded port, where the port is subjected to foreign material such as dust, dirt, metal shavings or the like, the foreign material is carried into the mating area between the external and internal threads as the bolt or fastener is threaded into the port. If foreign material is carried into the threads, galling and/or seizing usually results during assembly. This galling and seizing of the bolts causes substantial down time during an assembly operation, since the seized fastener must be removed, the hole cleaned out, and a replacement fastener installed.
Various types of fasteners have been utilized to eliminate the foreign material which would otherwise be carried into the mating area between the internal and external threads. These threaded bolts generally include a recess or space in its threads to enable the foreign material to accumulate in the recesses. Generally, a bolt includes a multiplicity of flutes or recesses which are equally spaced and extend deeply into the threads. Sometimes the flutes are formed at an angle with respect to the axis of the fastener. Also, some of these fasteners include pilot points to enable the fastener to easily enter the threaded ports.
While these types of fasteners are adequate for performing their function, designers are striving to improve the art.
SUMMARY OF THE INVENTION
The present invention provides the art with a fastener which, when entering a tapped port, accumulates foreign material that would otherwise be carried into the mating area between the external and internal threads. The invention provides recesses, approximately 180.degree. apart, which enable the material, when the fastener is threaded into the port, to receive the foreign material. The invention provides recesses or flutes which extend from the end of the pilot tip into at least the first full thread of the threaded shank portion of the bolt. Thus, the present invention provides a fastener which substantially prevents foreign material from being carried into the threads which, in turn, eliminates galling and seizing during assembly.
From the following detailed description taken in conjunction with the accompanying drawings and subjoined claims, other objects and advantages of the present invention will become apparent to those skilled in the art.